The use of Radio Frequency Identification (RFID) tags are quickly gaining popularity for use in the monitoring and tracking of an item. RFID technology allows a user to remotely store and retrieve data in connection with an item utilizing a small, unobtrusive tag. As an RFID tag operates in the radio frequency (RF) portion of the electromagnetic spectrum, an electromagnetic or electrostatic coupling can occur between an RFID tag affixed to an item and an RFID tag reader. This coupling is advantageous, as it precludes the need for a direct contact or line of sight connection between the tag and the reader.
A problem may be encountered when an RFID tag or other RF device is partially or fully isolated from an incoming RF signal, thereby inhibiting or preventing effective communications between the RF device and an interrogator. For example, consider the situation where an RFID tag is coupled to a box, the box being stacked on a pallet with other boxes so that the RFID tag is positioned somewhere towards the center of the stack of boxes. Further, assume that the boxes on the pallet contain some type of RF absorbing or RF reflective material. One can see the problem with effectively communicating with the RFID tag.
What is therefore needed is a way to communicate with RF devices, such as RFID tags, that are partially or fully isolated from an RF transmitting device.